One challenge of packaging electronic devices such as MEMS devices is that these devices have moving parts which require space or headroom within a package to allow for free movement of the moving parts. In some cases, these devices are sensitive to moisture and atmospheric pressure. Thus, these devices must be packaged in a hermetically sealed manner wherein the moisture and atmospheric pressure is tightly controlled if the devices are to function properly. Existing packages comprise a base section to which the MEMS device is mounted, and a cover section which is secured or joined to the base section to form a cover over the MEMS device. To achieve a hermetic seal, a sealing bead is formed at the interface or joint between the base section and the cover section.
The base section and the cover section may be singulated from a blank of suitable material before being joined. In order to create the headroom for the moving parts of the MEMS device, material may be removed from the cover section by a mechanical process such as grinding. Assembly of a package using the singulated base and cover sections requiring these components to be precisely aligned during an alignment operation that must be repeated for each package. Having to repeat the alignment operation for each package adds to the cost of fabricating the package.